1 /*
2  * Palmas USB transceiver driver
3  *
4  * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * Author: Graeme Gregory <gg@slimlogic.co.uk>
11  * Author: Kishon Vijay Abraham I <kishon@ti.com>
12  *
13  * Based on twl6030_usb.c
14  *
15  * Author: Hema HK <hemahk@ti.com>
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  */
22 
23 #include <linux/module.h>
24 #include <linux/interrupt.h>
25 #include <linux/platform_device.h>
26 #include <linux/err.h>
27 #include <linux/mfd/palmas.h>
28 #include <linux/of.h>
29 #include <linux/of_platform.h>
30 
31 static const char *palmas_extcon_cable[] = {
32 	[0] = "USB",
33 	[1] = "USB-HOST",
34 	NULL,
35 };
36 
37 static const int mutually_exclusive[] = {0x3, 0x0};
38 
39 static void palmas_usb_wakeup(struct palmas *palmas, int enable)
40 {
41 	if (enable)
42 		palmas_write(palmas, PALMAS_USB_OTG_BASE, PALMAS_USB_WAKEUP,
43 			PALMAS_USB_WAKEUP_ID_WK_UP_COMP);
44 	else
45 		palmas_write(palmas, PALMAS_USB_OTG_BASE, PALMAS_USB_WAKEUP, 0);
46 }
47 
48 static irqreturn_t palmas_vbus_irq_handler(int irq, void *_palmas_usb)
49 {
50 	struct palmas_usb *palmas_usb = _palmas_usb;
51 	unsigned int vbus_line_state;
52 
53 	palmas_read(palmas_usb->palmas, PALMAS_INTERRUPT_BASE,
54 		PALMAS_INT3_LINE_STATE, &vbus_line_state);
55 
56 	if (vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS) {
57 		if (palmas_usb->linkstat != PALMAS_USB_STATE_VBUS) {
58 			palmas_usb->linkstat = PALMAS_USB_STATE_VBUS;
59 			extcon_set_cable_state(&palmas_usb->edev, "USB", true);
60 			dev_info(palmas_usb->dev, "USB cable is attached\n");
61 		} else {
62 			dev_dbg(palmas_usb->dev,
63 				"Spurious connect event detected\n");
64 		}
65 	} else if (!(vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS)) {
66 		if (palmas_usb->linkstat == PALMAS_USB_STATE_VBUS) {
67 			palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
68 			extcon_set_cable_state(&palmas_usb->edev, "USB", false);
69 			dev_info(palmas_usb->dev, "USB cable is detached\n");
70 		} else {
71 			dev_dbg(palmas_usb->dev,
72 				"Spurious disconnect event detected\n");
73 		}
74 	}
75 
76 	return IRQ_HANDLED;
77 }
78 
79 static irqreturn_t palmas_id_irq_handler(int irq, void *_palmas_usb)
80 {
81 	unsigned int set, id_src;
82 	struct palmas_usb *palmas_usb = _palmas_usb;
83 
84 	palmas_read(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
85 		PALMAS_USB_ID_INT_LATCH_SET, &set);
86 	palmas_read(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
87 		PALMAS_USB_ID_INT_SRC, &id_src);
88 
89 	if ((set & PALMAS_USB_ID_INT_SRC_ID_GND) &&
90 				(id_src & PALMAS_USB_ID_INT_SRC_ID_GND)) {
91 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
92 			PALMAS_USB_ID_INT_LATCH_CLR,
93 			PALMAS_USB_ID_INT_EN_HI_CLR_ID_GND);
94 		palmas_usb->linkstat = PALMAS_USB_STATE_ID;
95 		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", true);
96 		dev_info(palmas_usb->dev, "USB-HOST cable is attached\n");
97 	} else if ((set & PALMAS_USB_ID_INT_SRC_ID_FLOAT) &&
98 				(id_src & PALMAS_USB_ID_INT_SRC_ID_FLOAT)) {
99 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
100 			PALMAS_USB_ID_INT_LATCH_CLR,
101 			PALMAS_USB_ID_INT_EN_HI_CLR_ID_FLOAT);
102 		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
103 		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", false);
104 		dev_info(palmas_usb->dev, "USB-HOST cable is detached\n");
105 	} else if ((palmas_usb->linkstat == PALMAS_USB_STATE_ID) &&
106 				(!(set & PALMAS_USB_ID_INT_SRC_ID_GND))) {
107 		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
108 		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", false);
109 		dev_info(palmas_usb->dev, "USB-HOST cable is detached\n");
110 	} else if ((palmas_usb->linkstat == PALMAS_USB_STATE_DISCONNECT) &&
111 				(id_src & PALMAS_USB_ID_INT_SRC_ID_GND)) {
112 		palmas_usb->linkstat = PALMAS_USB_STATE_ID;
113 		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", true);
114 		dev_info(palmas_usb->dev, " USB-HOST cable is attached\n");
115 	}
116 
117 	return IRQ_HANDLED;
118 }
119 
120 static void palmas_enable_irq(struct palmas_usb *palmas_usb)
121 {
122 	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
123 		PALMAS_USB_VBUS_CTRL_SET,
124 		PALMAS_USB_VBUS_CTRL_SET_VBUS_ACT_COMP);
125 
126 	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
127 		PALMAS_USB_ID_CTRL_SET, PALMAS_USB_ID_CTRL_SET_ID_ACT_COMP);
128 
129 	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
130 		PALMAS_USB_ID_INT_EN_HI_SET,
131 		PALMAS_USB_ID_INT_EN_HI_SET_ID_GND |
132 		PALMAS_USB_ID_INT_EN_HI_SET_ID_FLOAT);
133 
134 	if (palmas_usb->enable_vbus_detection)
135 		palmas_vbus_irq_handler(palmas_usb->vbus_irq, palmas_usb);
136 
137 	/* cold plug for host mode needs this delay */
138 	if (palmas_usb->enable_id_detection) {
139 		msleep(30);
140 		palmas_id_irq_handler(palmas_usb->id_irq, palmas_usb);
141 	}
142 }
143 
144 static int palmas_usb_probe(struct platform_device *pdev)
145 {
146 	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
147 	struct palmas_usb_platform_data	*pdata = dev_get_platdata(&pdev->dev);
148 	struct device_node *node = pdev->dev.of_node;
149 	struct palmas_usb *palmas_usb;
150 	int status;
151 
152 	palmas_usb = devm_kzalloc(&pdev->dev, sizeof(*palmas_usb), GFP_KERNEL);
153 	if (!palmas_usb)
154 		return -ENOMEM;
155 
156 	if (node && !pdata) {
157 		palmas_usb->wakeup = of_property_read_bool(node, "ti,wakeup");
158 		palmas_usb->enable_id_detection = of_property_read_bool(node,
159 						"ti,enable-id-detection");
160 		palmas_usb->enable_vbus_detection = of_property_read_bool(node,
161 						"ti,enable-vbus-detection");
162 	} else {
163 		palmas_usb->wakeup = true;
164 		palmas_usb->enable_id_detection = true;
165 		palmas_usb->enable_vbus_detection = true;
166 
167 		if (pdata)
168 			palmas_usb->wakeup = pdata->wakeup;
169 	}
170 
171 	palmas->usb = palmas_usb;
172 	palmas_usb->palmas = palmas;
173 
174 	palmas_usb->dev	 = &pdev->dev;
175 
176 	palmas_usb->id_otg_irq = regmap_irq_get_virq(palmas->irq_data,
177 						PALMAS_ID_OTG_IRQ);
178 	palmas_usb->id_irq = regmap_irq_get_virq(palmas->irq_data,
179 						PALMAS_ID_IRQ);
180 	palmas_usb->vbus_otg_irq = regmap_irq_get_virq(palmas->irq_data,
181 						PALMAS_VBUS_OTG_IRQ);
182 	palmas_usb->vbus_irq = regmap_irq_get_virq(palmas->irq_data,
183 						PALMAS_VBUS_IRQ);
184 
185 	palmas_usb_wakeup(palmas, palmas_usb->wakeup);
186 
187 	platform_set_drvdata(pdev, palmas_usb);
188 
189 	palmas_usb->edev.supported_cable = palmas_extcon_cable;
190 	palmas_usb->edev.dev.parent = palmas_usb->dev;
191 	palmas_usb->edev.mutually_exclusive = mutually_exclusive;
192 
193 	status = extcon_dev_register(&palmas_usb->edev);
194 	if (status) {
195 		dev_err(&pdev->dev, "failed to register extcon device\n");
196 		return status;
197 	}
198 
199 	if (palmas_usb->enable_id_detection) {
200 		status = devm_request_threaded_irq(palmas_usb->dev,
201 				palmas_usb->id_irq,
202 				NULL, palmas_id_irq_handler,
203 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING |
204 				IRQF_ONESHOT | IRQF_EARLY_RESUME,
205 				"palmas_usb_id", palmas_usb);
206 		if (status < 0) {
207 			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
208 					palmas_usb->id_irq, status);
209 			goto fail_extcon;
210 		}
211 	}
212 
213 	if (palmas_usb->enable_vbus_detection) {
214 		status = devm_request_threaded_irq(palmas_usb->dev,
215 				palmas_usb->vbus_irq, NULL,
216 				palmas_vbus_irq_handler,
217 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING |
218 				IRQF_ONESHOT | IRQF_EARLY_RESUME,
219 				"palmas_usb_vbus", palmas_usb);
220 		if (status < 0) {
221 			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
222 					palmas_usb->vbus_irq, status);
223 			goto fail_extcon;
224 		}
225 	}
226 
227 	palmas_enable_irq(palmas_usb);
228 	device_set_wakeup_capable(&pdev->dev, true);
229 	return 0;
230 
231 fail_extcon:
232 	extcon_dev_unregister(&palmas_usb->edev);
233 
234 	return status;
235 }
236 
237 static int palmas_usb_remove(struct platform_device *pdev)
238 {
239 	struct palmas_usb *palmas_usb = platform_get_drvdata(pdev);
240 
241 	extcon_dev_unregister(&palmas_usb->edev);
242 
243 	return 0;
244 }
245 
246 #ifdef CONFIG_PM_SLEEP
247 static int palmas_usb_suspend(struct device *dev)
248 {
249 	struct palmas_usb *palmas_usb = dev_get_drvdata(dev);
250 
251 	if (device_may_wakeup(dev)) {
252 		if (palmas_usb->enable_vbus_detection)
253 			enable_irq_wake(palmas_usb->vbus_irq);
254 		if (palmas_usb->enable_id_detection)
255 			enable_irq_wake(palmas_usb->id_irq);
256 	}
257 	return 0;
258 }
259 
260 static int palmas_usb_resume(struct device *dev)
261 {
262 	struct palmas_usb *palmas_usb = dev_get_drvdata(dev);
263 
264 	if (device_may_wakeup(dev)) {
265 		if (palmas_usb->enable_vbus_detection)
266 			disable_irq_wake(palmas_usb->vbus_irq);
267 		if (palmas_usb->enable_id_detection)
268 			disable_irq_wake(palmas_usb->id_irq);
269 	}
270 	return 0;
271 };
272 #endif
273 
274 static SIMPLE_DEV_PM_OPS(palmas_pm_ops, palmas_usb_suspend, palmas_usb_resume);
275 
276 static struct of_device_id of_palmas_match_tbl[] = {
277 	{ .compatible = "ti,palmas-usb", },
278 	{ .compatible = "ti,palmas-usb-vid", },
279 	{ .compatible = "ti,twl6035-usb", },
280 	{ .compatible = "ti,twl6035-usb-vid", },
281 	{ /* end */ }
282 };
283 
284 static struct platform_driver palmas_usb_driver = {
285 	.probe = palmas_usb_probe,
286 	.remove = palmas_usb_remove,
287 	.driver = {
288 		.name = "palmas-usb",
289 		.of_match_table = of_palmas_match_tbl,
290 		.owner = THIS_MODULE,
291 		.pm = &palmas_pm_ops,
292 	},
293 };
294 
295 module_platform_driver(palmas_usb_driver);
296 
297 MODULE_ALIAS("platform:palmas-usb");
298 MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
299 MODULE_DESCRIPTION("Palmas USB transceiver driver");
300 MODULE_LICENSE("GPL");
301 MODULE_DEVICE_TABLE(of, of_palmas_match_tbl);
302